SB2018010203 - Multiple vulnerabilities in NetBSD



SB2018010203 - Multiple vulnerabilities in NetBSD

Published: January 2, 2018

Security Bulletin ID SB2018010203
Severity
Low
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 secuirty vulnerabilities.


1) Privilege escalation (CVE-ID: N/A)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a missing mask in a syscall in in sys/arch/sparc64/sparc64/compat_13_machdep.c on sparc64 architecture. A local unprivileged user can set privileged bits, such as PSTATE_PRIV in the %pstate register and gain escalated privileges on the system.

2) Privilege escalation (CVE-ID: N/A)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to an error in compat_linux32 when handling GDT on amd64 system in sys/compat/linux32/arch/amd64/linux32_machdep.c. A local unprivileged user can create a condition where a page fault is generated if a segment register is reloaded with a "high" selector, located near the end of the GDT, and gain root access to the system.

3) Improper input validation (CVE-ID: N/A)

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to an input validation error in sys/arch/i386/i386/i386_trap.S (for NetBSD 7.x) or sys/arch/i386/i386/vector.S (for NetBSD 6.x) when the #UD exception handler is implicitly using the %ds register, before it actually initialized it to the kernel value. A local unprivileged user can crash the system.

Remediation

Install update from vendor's website.